Inscription was once a new profession for Wrath of the Lich King. Later on, Blizzard decided to move the profession from WotLK to patch 3.0.2 (the earliest live patch in the 3.X.Y series). For Inscription you must at least have a TBC account. Hans Kamp (talk) 12:30, 6 November 2008 (UTC)
Probably safer and less confusing to just leave out the icons in this case (/).
Inscription is a feature of Wrath. It was introduced in the Wrath setup patch. If you seriously believe that inscription is not a WotLK feature then Draenei, Blood Elves, Horde Paladins, Alliance Shamans, and Jewelcrafting are all vanilla features because they were introduced and implemented with the 2.0.whatever patch.
The difference is that you need the Burning Crusade expansion to access all of those. You do not need to have Wrath of the Lich King to learn Inscription.
And that is exactly my point. You need WotLK for the rest of the features, mentioned by Jows. Inscription was meant to be a part of WotLK, but it was moved out of it, and made available in World of Warcraft 3.0. The upcoming changes in the zones are visible in the Cataclysm trailer but will be a part of 4.0, a similar point. Goblins, Worgen and level 78-85 areas (not Storm Peaks and Icecrown though) requires Cataclysm.
So when Cata drops and the entire world is remade, is the new world going to be marked as "vanilla" content despite it being the MAJOR point of the entire expansion?